Page:The birds of America, volume 7.djvu/29

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THE FRIGATE PELICAN.
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side going to the bronchial membrane. The bronchi are wide, and formed of 20 half rings.

The sternum is extremely singular, on account of its great width and concavity, compared with its length; the latter being only 2i inches, while the breadth at the anterior costal pi*ocesses is Z inches. The crest is thus extremely short, but of considerable height, its most prominent part being 10^ twelfths. The coracoid bones are remarkably large, and so firmly fixed in the joint as to have just the slightest perceptible motion. The furcula is also very large and wide, of the form of the letter U, its crura at their union forming a large mass of solid bone, continuous with the crest of the sternum. The posterior edge of the sternum has a very slight sinus on each side. Now, in this bird, which is confessed to be inferior to none in its power of flight, the sternal crest is not nearly so prominent as that of a Grouse or Partridge, so that the supposed indication which this part affords of vigorous flight is evidently fallacious. The sternum, although much shorter, resem- bles that of the Pelicans, Cormorants, and Anhingas, as well as in a less degree that of the Gannets.

Genus IV.— PELECANUS, Linn. PELICAN.

Bill about thrice the length of the head, rather slender, almost straight, depressed; upper mandible linear, depressed, convex at the base, gradually flattened, and a little enlarged to near the end, when it narrows, and termi- nates in a hooked point; ridge broad and convex at the base, gradually nar- rowed and flattened beyond the middle, separated by a groove from the sides, erect at the base, sloping towards the edges, edges very acute, with an internal groove; lower mandible with the angle excessively long, extending to the unguis, the sides erect and convex, the edges thin and involute, the ip decurved. Nostrils basal, lateral, linear, concealed by the wrinkles of he skin. Head small, oblong; neck long, stout; body full, rather flattened. Feet short, and very stout; tarsus short, compressed, covered all round with hexagonal scales; toes in the same plane, all connected by webs, first shortest, fourth longer than third. Claws short, strong, curved, that of the third